<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        var arr= [
            {
                id:1001
            },
            {
                id:1002
            }
        ];
        var id = 1002;
        var index = arr.findIndex(item=>item.id == id);
        console.log(index)//1
    </script>
</body>
</html>